I leveled five characters to 50 and used MQ on all of them. Map, gate, short warps and target. My first character I made a /tar wisp and just did that like a whole weekend at level 10-15...no issues. Used map and target to make thousands of pp killing cyclopses, two boxed all the time, pl'd etc.
I had one character banned recently, I'm thinking is was MQ unrelated. Not sure what the deal is, I never even asked. I had some dragon loot that I was trying to sell and made some coments about people plat duping or something, I don't know.